Abstract While there have been new breakthroughs in the design of effective HIV risk-reduction interventions for African American adolescent females, an adolescent subgroup at high risk of HIV, there are no published maintenance strategies with demonstrated evidence of effectiveness in sustaining newly acquired HIV- preventive behaviors over protracted periods of time. While showing a capacity to reduce HIV-associated risk behaviors, many HIV interventions also report observing decay in treatment effects over time. Unfortunately, for behavior change to be meaningful, it must be enduring. Thus, this 3.5 year renewal application proposes to continue the parent study HIV Prevention Maintenance for African American Teens (1R01 MH070537), a randomized controlled trialevaluating the efficacy of an HIV prevention maintenance strategy, tailored telephone-delivered HIV prevention education sessions, relative to a time-equivalent comparison (telephone-delivered general health promotion education sessions), to sustain the effects of a CDC-defined evidence-based, group-delivered HIV intervention (known as SiHLE), in reducing incident STDs and enhancing condom-protected vaginal sex acts among African-American adolescent females over an 18-month follow-up period. This research design provides a conceptually and methodologically rigorous evaluation of the HIV prevention maintenance strategy. The impetus for the renewal is an interim data analysis observing promising treatment advantages for the HIV prevention maintenance strategy for the primary biological and behavioral outcomes over an 18- month follow-up: (1) a significant reduction in laboratory-confirmed incident STDs (OR=.56; P= .03); and (2) a significant effect in amplifying percent condom-protected vaginal sex acts (11% relative mean difference; P=.03). The renewal will: (1) permit continued implementation of the HIV prevention maintenance strategy (HIV prevention telephone-delivered education sessions) and the attention comparison (telephone-delivered general health promotion education sessions), and (2) extend the follow- up an additional 18-month (adding assessments at 24-, 30-, and 36-months). The innovation of the proposed renewal application is that we will: (1) have a markedly longer follow-up period of 36-months to assess the efficacy of the maintenance strategy in reducing the primary biological outcome, incident STDs, and in enhancing the primary behavioral outcome, proportion of condom-protected vaginal sex acts; (2) have a prospective cost evaluation analysis to gauge the cost-effectiveness of the maintenance strategy in averting new STDs and enhancing condom use; and (3) conduct a moderation analysis modeling the effect of dose of the telephone-delivered education session received on key biological and behavioral outcomes as well as HIV-prevention mediators. The proposed renewal can advance the field of HIV prevention science and provide another tool to help reduce adolescents' risk for HIV. Relevance of the Research to Public Health There is an absence of effective maintenance strategies designed to sustain HIV prevention intervention effects for African-American adolescent females. The present study could be amongst the first maintenance interventions designed for this vulnerable population that uses both behavioral and biological outcomes and cost evaluation analysis, over a 36-month follow-up period, to assess programmatic efficacy and cost- effectiveness. The proposed study has the potential to significantly impact the intersecting HIV and STD epidemics among African-American adolescent females.